The present embodiments relate generally to non-destructive inspection methods and, more particularly, to the use of infrared thermography to inspect components of gas turbine engines.
Components of gas turbine engines can be exposed to harsh environments, including high temperatures, which can cause damage to components during operation and reduce a component's effective life cycle. Some turbine components can be cooled during operation to limit damage and limit thermal growth of the component, which can be required for particular applications. Components can be cooled by a cooling fluid applied to a surface of the component or through internal cooling channels. The assessment of a component's cooling efficiency during an inspection process can be used to predict the performance of components within a representative environment during operation. A variety of techniques have been used to assess cooling efficiency, including measuring a cooling fluid flow through a component as well as visual inspection of cooling channels and non-destructive imaging. Thermal inspection of components using infrared thermography has been used to assess cooling effectiveness, however, has generally been limited to point to point spot checks, or pixel by pixel measurements without accounting for three-dimensional spatial variations. Such methods are not capable of providing an accurate measurement of surface temperatures over a three-dimensional surface.